The Robustness Design Of Portal Frame Column Foot Structure Under Extreme Snow Load

The light portal frame structure system is one of the most popular kinds of structureforms at application of steel structure in our country. It gets the favor at home and abroadwith light quality, beautiful and easy installation. But in recent years global extremeweather is flooding and natural disasters is increasing year by year. Especially in the caseof a rare blizzard, the overall degree of safety of the light steel structure is not high,resistance to overload ability is poor, and the light steel structure is sensitive to snow load.It will cause serious consequences, bring a serious threat to human life and property.Therefore, the research of the collapse of portal frame under extreme snow loads is verynecessary and meaningful. This article is aimed at pedestal structure aspects, andaccording to the geometrical size of the component and material performance into account,and analysis the collapse of plane rigid frame.Robust optimization analysis was carried out on the frame and analysis the collapseof plane rigid frame in the selection of two kinds of structure under working state. Thestructure of two kinds of working state are respectively the structure bearing capacity limitstate of rules and regulations and extreme snow load leads to structural collapse criticalstate. The main research content is as follows: Establishing finite element model which issuitable for the simulation of the structural collapse destroyed, choosing two kinds ofcontrollable factors and five kinds of uncontrollable factors, analysis of multiple factorsframe structure under the influence of different working condition. Using Box-Behnkenexperiment design method, the response surface model is established. Through carrying onthe significance test of the response surface model, the analysis shows the selected factorsimpact on the different working conditions of frame structure size. Using the robustoptimization theory to get the characteristics of the response surface function model forfurther analysis, and the result shows the most optimal point is not in the test area. Whenthe most optimal point is not in the test area, it can be replaced with the robustness pointusing the maximum signal to noise ratio. Ensure optimal design point within the scope ofthe design factors allowed and make the optimization design more sense. The result was the best combination of various factors. In view of the ultimate bearing capacity of framestructure and extreme bearing capacity of two damage state analysis, this article get therobust design of the column foot structure of frame structure.